<template>
  <div class="bottom-menu">
    <CheckButton
      class="select-all"
      @checkBtnClick="checkBtnClick"
      v-model="isSelectAll"
    ></CheckButton>
    <span>全选</span>
    <span class="total-price">合计: ¥{{ totalPrice }}</span>
    <span class="buy-product">去计算({{ cartLength }})</span>
  </div>
</template>

<script>
import CheckButton from "./CheckButton";
import { mapGetters } from "vuex";

export default {
  name: "BottomBar",
  components: {
    CheckButton
  },
  computed: {
    ...mapGetters(["cartLength", "cartList"]),
    //* 总价格计算
    totalPrice() {
      const cartList = this.cartList;
      return cartList
        .filter(item => {
          return item.checked;
        })
        .reduce((preValue, item) => {
          return preValue + item.count * item.newPrice;
        }, 0)
        .toFixed(2);
    },
    //* 判断是否全选
    isSelectAll: function() {
      if (this.cartList.length === 0) return false;

      return this.cartList.find(item => item.checked === false) === undefined;
    }
  },
  methods: {
    checkBtnClick: function() {
      // 1.判断是否有未选中的按钮
      let isSelectAll = this.cartList.find(
        item => !item.checked
      );

      // 2.有未选中的内容, 则全部选中
      if (isSelectAll) {
        this.cartList.forEach(item => {
          item.checked = true;
        });
      } else {
        this.cartList.forEach(item => {
          item.checked = false;
        });
      }
      
    }
  }
};
</script>

<style scoped>
.bottom-menu {
  width: 100%;
  height: 44px;
  background-color: #eee;
  position: fixed;
  bottom: 50px;
  left: 0;
  box-shadow: 0 -2px 3px rgba(0, 0, 0, 0.2);
  font-size: 14px;
  color: #888;
  line-height: 44px;
  padding-left: 35px;
  box-sizing: border-box;
}

.bottom-menu .select-all {
  position: absolute;
  line-height: 0;
  left: 12px;
  top: 13px;
}

.bottom-menu .total-price {
  margin-left: 15px;
  font-size: 16px;
  color: #666;
}

.bottom-menu .buy-product {
  background-color: orangered;
  color: #fff;
  width: 100px;
  height: 44px;
  text-align: center;
  line-height: 44px;
  float: right;
}
</style>
